Do photorejuvenation skin instead of darkening, may be hyperpigmentation, may also be the phenomenon of reverse color. 1. Hyperpigmentation: the process of photon will cause trauma to the skin. In the process of skin recovery, there may be an inflammatory reaction, the formation of post-inflammatory hyperpigmentation, resulting in dark skin color after photorejuvenation. 2. Reflective phenomenon: When photorejuvenation uses a laser, the melanin inside the pigmentation absorbs the light and heat and instantly bursts off, resulting in the blackening of the surface of the skin, which belongs to the phenomenon of anticolor. After photorejuvenation, it is recommended to pay strict attention to sun protection to avoid sun exposure resulting in hyperpigmentation. Also pay attention to skin moisturizing, avoid skin dryness. If hyperpigmentation exists for a long time, or other uncomfortable symptoms appear on the skin, it is recommended to go to the hospital in time, and choose the appropriate treatment under the guidance of the doctor.